Cloth folding machine



R. s. GAMBLE ET AL CLOTH FOLDING MACHINE July 29, 195s 3 Sheets-Sheet 1 Filed Dec. 12, 1955 INVENTORL RALPH s. GAMBLE-.- ,LELAND F. REMINGTON.

V ATTY.

-R. s'. GAMBLE 'ETAL Q 2,845,265-

Jul 29, 1958.

I CLOTH FOLDING MACHINE 3 Sheets-Sheet 2 Filed D95. 12, 1955 u y 8 R. s. GAMBLE ETAL 2,845,265

- CLOTH FOLDINF MACHINE Filed Dec. 12, 1955 v :s Sheets-Sheet 3 ch LL l l b l T .d g T 3: 0 m

d l g 5 5 I s I I: I g

m INVTOR. RALPH s. GAMBLE YLELAND F. REMINGTON.-

ATTY

States atent ()fiiice Patented July 29, 1958 CLOTH FOLDING MACHINE Application December 12, 1955, Serial No. 552,372 7 Claims. (Cl. 270-79) This invention relates to machines for folding long pieces of cloth in superposed layers. Such folding is commonly accomplished by means of a folding blade which presents the folded edges of the cloth to opposed pairs of clamping jaws alternately.

Each pair of clamping jaws comprises an upper fixed jaw and a lower movable jaw, and the movable jaws are yieldingly pressed against the fixed jaws by suitable air pressure. The air pressure on each lower jaw is momentarily overcome each time that a new fold of cloth is presented thereto.

An important feature of our invention relates to the provision of improved means for maintaining the desired clamping pressure on the superposed folds, while at the same time accommodating an increasing height or thickness of folded cloth. In the preferred construction, this progressive adjustment to cloth load is very simply effected by hydraulic means. I

Another object of the invention relates to the provision of means for causing the machine to stop only at a predetermined point in the folding cycle.

Our invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

A preferred form of the invention is shown in the drawings, in which:

Fig. 1 is a side elevation of our improved folding machine, with certain parts shown in section;

Fig. 2 is a partial front elevation, looking in the direction of the arrow 2 in Fig. 1;

Fig. 3 is an enlarged elevation, partly in section, and showing our improved operating and control mechanism;

Fig. 4 is an enlarged and partly diagrammatic side elevation of the pneumatic and hydraulic control mechanism and associated parts, and with certain parts shown in section;

Fig. 5 is a sectional side elevation of a solenoidoperated valve;

Fig. 6 is a sectional side elevation of a check valve;

Fig. 7 is a detail plan view of a portion of the cloth table and its supporting structure, looking in the direction of the arrow 7 in Fig. 1; and

Fig. 8 is a detail side elevation, looking in the direction of the arrow 8 in Fig. 7.

Referring to Figs. 1 and 2, our improved folding machine comprises a frame F having a cloth table 10, the transverse edges of which are supported on cross-bars and 16 (Fig. 3). The cross-bars 15 and 16 have brackets 11 (Figs. 7 and 8) which are slidable in vertical fixed and grooved guide-bars 12.

The cross-bars 15 and 16 are pivotally connected to the opposite ends of a supporting lever 18, which lever in turn is pivoted at 19 to the'upper end of a piston rod 20. The rod 20 has a piston 21 (Fig. 3) vertically slidable in a pivoted cylinder 22 which is supplied with air under pressure through a feed pipe 24, shut-off valve 25, and supply pipe 26. The valve 25 also has a vent or waste-pipe 27 and may be foot-operated.

The cross-bars 15 and 16 are provided with movable lower clamping jaws 30 and 31 which press the folded edges of the cloth upward against fixed upper clamping jaws 32 and 33.

The cloth C is threaded through a folding blade 36 clearly shown in section in Fig. 3. The blade 36 has swivel bearings at the upper ends of a pair of supporting arms 40 mounted to swing about swivel bearings 42 in the frame F. A collar 44 is fixed at an intermediate point on each supporting arm 40, and each collar 44 isv connected by a link 46 (Fig. 3) to a crank arm 47 mounted on a crankshaft 48.

The crankshaft 48 is continuously rotated by a motor M connected thereto by a belt or chain 50. As the crankshaft rotates, the folding blade 36 is oscillated between predetermined limits. As the blade 36 is oscillated, it is also swiveledby guide-rods 52 (Fig. 1) which swing freely about fixed pivots 53. The cloth is supplied to the folding blade from a rotated cloth roll K through feed rolls 55 and 56 and a scray 57. p

The parts thus far described are in general of the usual construction, and the only novel feature thus far involved is the attachment of the collars 44 (Fig. 3) at intermediate points on the swinging arms 40, rather than at the extreme upper ends as has been the previous practice. An easier and more uniform motion of the folding blade 36 is thus attained. a

Each cross-bar 15 and 16 is pivotally connected at the center of its length to the upper end of a piston rod 60 (Fig. 3) which is connected to a piston 61 mounted in a vertically slidable cylinder 62. Special provision is made for supplying oil to the space S between each piston 61 and the upper end of the associated cylinder 62, as will be hereinafter described.

A collar 64 (Fig. 3) is clamped to each cylinder 62 intermediate its ends, and a cam lever 66 is pivoted at 67 to each collar 64. At its opposite end, each cam lever 66 is provided with a roll 68 engaged by a cam 69 mounted on a cam shaft 70. Each cam lever 66 is adjustably secured at 71 to a bracket which is pivoted at 71a to a fixed stand 72. Each lever 66 is yieldingly pressed upward by a coil spring 74.

The cam shafts have sprocket-and-chain connections 76 with each other and also have a chain connection 77 with the crankshaft 48. The cam shafts 70 and crankshaft 48 thus rotate in unison and at the same speed, but the two cams 69 are mounted 180 apart, so that they alternately lift the rolls 68 on the levers 66, and alternately depress the associated movable lower clamping jaws 30 or 31.

As each spring 74 moves the associated cyinder 62 upward, the piston rod 60 and piston 61 will be moved npwar'd with the table 10 by the air pressure in the cylinder 22. When a cam 69 operates a lever 66, the associated cylinder 62 is moved positively downward and forces the piston 61 and piston rod 60 downward, due to the fact that'oil is trapped in the space S. This depresses the associated lower jaw 30 or 31.

The amount of oil in each space S must be progressively increased as the pile of cloth on the table 12 increases in thickness, in order to maintain normal opera tion and pressure relief for cloth insertion.

For this purpose, the space S at the upper end of each cylinder 62 is connected by a pipe 80 or 81 and a branch-pipe 81a to a tank or reservoir T containing oil under low pressure, as five pounds. Check valves 82 are provided in the pipes 80 and 81 and permit passage of oil toward each cylinder 62 but not in a reverse direction.

As the thickness of cloth on the table 10 increases, the upward travel of the piston 61 will be stopped at progressively lower levels, While the upward travel of the associated cylinder 62 will continue to a fixed upper limit. This will increase the depth of the space S and a corresponding amount of make-up oil will be forced into this increased space fromthe'tank T through one of the check valves 82 and the pipe"80 or 81. The space S is thus kept constantly fullof oil, and the piston 61 and associated clamping jaw 30 or 31 is drawn downward a uniform and desired distance at each revolution of the associated cam 69.

The locus of travel of the cross-bar or 16 and of each lower clamping jaw or 31 may thus be progressively shifted downward, while at the same time the relief of pressure for cloth insertion is uniformly maintained.

The control mechanism and connections through which the described results are attained 'are best shown in Figs. 4 to 6.

Air under substantial pressure is supplied from a pipe 84 (Fig. 4) through a manual shut-off valve 85. The air passes through a suitable strainer 86 to a pressureregulating valve 87 which is commonly set to provide approximately fifty pounds pressure in the distribution pipe 88. This air then passes through a suitable air-lubricating device 89 to a T 90 to which the air cylinder supply pipe 26 is connected.

Air under relatively heavy pressure is thus supplied through the valve 25 to the air cylinder 22.

A pipe 91 connects the T 90 through a pressure-regulating valve 92 to a second tee 93. The regulating valve 92 is set to deliver air at relatively low pressure, which may be on the order of five pounds.

The T 93 is connected through a normally-closed shut-off valve 94 and pipe 95 to the pipe 81 which supplies oil to the space S in one'of thecylinders 62, and the T 93 is similarly connected through a normallyclosed shut-off valve 96 and a pipe 97 to the pipe 81 which supplies oil to the space S in the other cylinder 62.

The T 93 is also connected through a branch pipe 98 to the upper end of the tank T, and a safety and filler valve 99 may be provided adjacent the solenoid-operated shutoff valve 96.

One of the shut-01f valves, as 96, is shown in detail in Fig. 5 and is to be inserted between the upper end of the pipe 97 and the safety valve 99.

The valve 96 comprises a port 100 normally closed by a solenoid plunger 101 forced upward to close the port by a coil spring 102.

The details of the valve 96 form no part of the present invention.

The plunger 101 is drawn downward to open the valve 96 when the solenoid coil 103 is energized. The coil 103 is connected to line wires 104 and 105 (Fig. 4) to which branch wires 106 and 107 from the solenoid-operated shut-off valve 94 are also connected.

Whenever a circuit is completed through the wires 104 r:

and 105, the shut-off valves 94 and 96 are simultaneously opened, but otherwise they are normally closed.

A normally-open pressure-operated switch 110 in the wire 104 is connected by a pipe 111 to the pipe 24 leading to the air cylinder 22. A normally-closed pressureoperated switch 114 in the wire 104 is also connected to the pipe 111.

When air is admitted to the air cylinder 22 to raise the table at the start of a folding operation, the pressure will rise slowly and air under five pounds pressure through the pipe 111 will close the switch 110 and thus open the valves 94 and 96. This permits oil to return from the spaces S in the oil cylinders 62 to the oil tank T, and permits the pistons 61 and the associated lower jaws 30 and 31 to be moved upward with the table '10 to their extreme upper or starting positions.

As the pressure in the air-cylinder 22 rises, it moves the lever 18 (Fig. 3) and connected pistons 61 more strongly upward and overcomes the normal five-pound pressure in the tank feed pipe 98.

As soon as the table reaches its extreme upward position, the air pressure will build up in the pipe 24 and cylinder 22 to the regulated high pressure, as fifty pounds.

The pressure-operated switch 114 will then be opened to break the solenoid valve circuit.

The solenoid valves then close, so that no further escape of oil from the spaces S in the cylinders 62 can take place, but make-up oil can thereafter be supplied to the spaces S through the check valves 82 previously described.

The motor M is controlled by a main switch (Fig. 4) adapted to be closed by a solenoid 121 when the solenoid circuit is closed by a switch 122. A second switch 123 in a shunt circuit 124 is normally open when the machine is at rest. The switch 123 overlies a collar 125 mounted on or associated with the shaft 70 (Fig. 3) which supports one of the earns 69.

The collar 125 normally engages and closes the switch 123 but has a flat side at one point in its periphery. At this point, the switch 123 will be opened by a spring 126 and the motor M will stop.

If now the switch 122 is closed, the main switch 120 will be closed and the motor will again operate as long as the switch 122 remains closed. When it is desired to stop the machine, the switch 122 is opened but the collar 125 will hold the switch 123 closed unless and until the flat side of the collar is uppermost.

The parts are so associated that the flat side will be uppermost when the folding blade 36 is in mid position and is moving away from the front clamping jaws 30 and 32. It is found that the cloth can be most conveniently cut and removed from the table 10 when the folding blade is stopped in the described position.

Any suitable brake mechanism may be provided for the motor M, so that the machine will stop promptly when the switch 123 is opened. 7

In Fig. 6, we have shown a ball-type check valve 130 which may be substituted for the more conventional check valves 82 shown in Fig. 3.

The general operation is believed to be clearly apparent from the foregoing detailed description. The shut-off valve 85 is opened to admit air to the regulating valves 87 and 92 and a double switch is closed in the line wires L and L. The air valve 25 is then opened to connect the air supply to the table-lifting cylinder 22. The solenoid-operated valves 94 and 96 are energized by the closing of the switch 110 at relatively low pressure and this vents the spaces S at the upper ends of the cylinders 62, as described. As this venting operation is completed, the increasing air pressure in the air system opens the switch 114 and thus allows the valves 94 and 96 to close and to thereafter remain closed during the operation of the machine.

The motor M is then started by the switch 122 and operates the folding machine in the usual manner, and make-up oil is promptly supplied to the spaces S as the pile of cloth on the table 10 increases in thickness.

Having thus described our invention and the advantages thereof, we do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what we claim is:

1. In a cloth folding machine, a depressible cloth table having spaced edge portions, a pair of fixed upper cloth-clamping jaws and a pair of movable lower clothclamping jaws, all associated with said spaced edge portions, a cloth-folding blade mounted to swing back-andforth over said table and from edge to edge thereof, means to continuously oscillate said blade from one edge portion to the other of said table in a folding cycle effective to fold and deposit the cloth in superposed layers on'said table and to insert the edges of the cloth folds between said upper and lower clamping jaws, means to normally and yieldingly maintain said table edge portions and said lower clamping jaws in elevated cloth-clamping position, a separate hydraulic device operatively connected to each lower clamping jaw and to the associated table edge portion and efiective to depress said jaw and said edge portion a predetermined distance, control mechanism therefor effective to selectively activate each hydraulic device separately and alternatively to depress the associated table edge portions and movable clamping jaws to release the associated cloth edge portions to permit insertion of additional cloth folds, and means to progressively shift downward the locus of the lower limit of depression of each movable clamping jaw and associated table edge portion as the thickness of the load of folded cloth increases.

2. The combination in a cloth folding machine as set forth in claim 1, in which a container for make-up oil under pressure is connected to each hydraulic device, and in which means is provided to intermittently admit relatively small portions of said make-up oil to each hydraulic device to offset the increasing thickness of the pile of folded cloth on the associated edge portions of the table.

3. The combination in a cloth folding machine as set forth in claim 2, in which means is provided to release said make-up oil from said hydraulic device in order to permit the lower jaws to return to initial raised position, and in which said releasing means is automatically operative to release the make-up oil from said hydraulic device after a load of folded cloth is removed from the table and prior to a new folding operation.

4. The combination in a cloth folding machine as set forth in claim 2, in which means is provided to release said rnake-up oil from said hydraulic device in order to permit the lower jaws to return to initial raised position, and in which said releasing means is automatically operative to release the make-up oil from said hydraulic device after a load of folded cloth is removed from the table and prior to a new folding operation, and in which the means to admit and to thereafter release the makeup oil for each hydraulic device comprises a separate branched pipe circuit for the make-up oil, which circuit has a check valve in one branch thereof opening towards said device only, and having a normally-closed valve in the other branch.

5. The combination in a cloth folding machine as set forth in claim 2, in which means is provided to release said make-up oil from said hydraulic device in order to permit the lower jaws to return to initial raised position, and in which said releasing means is automatically operative to release the make-up oil from said hydraulic device after a load of folded cloth is removed from the table and prior to a new folding operation, and in which the means to admit and to thereafter release the make-up oil for each hydraulic device comprises a separate branched pipe circuit for the make-up oil, which circuit has a check valve in one branch thereof opening towards said device only, and having a normally-closed valve in the other branch, and in which automatic means is provided to briefly open said normally-closed valve on initially starting said machine, and in which additional automatic means is provided to promptly thereafter close said valve.

6. In a cloth folding machine, a depressible cloth table having spaced edge portions, a pair of fixed upper clothclamping jaws and a pair of movable lower cloth-clamping jaws, all associated with said spaced edge portions, a cloth-folding blade mounted to swing back-and-forth over said table and from edge to edge thereof, means to continuously oscillate said blade from one edge portion to the other of said table in a folding cycle effective to fold and deposit the cloth in superposed layers on said table and to insert the edges of the cloth folds between said upper and lower clamping jaws, means to normally and yieldingly maintain said table edge portions and said lower clamping jaws in elevated cloth-clamping position, and electric means to drive said folding machine which comprises a branched control circuit for said electric means, a manually operable stop switch in one branch of said circuit which is closed to maintain the folding operation active and which is opened to stop the machine, a second switch in the second branch of said control circuit which provides a shunt operating control for said electric means and which maintains said electric means operative after said first switch is opened until said second switch is also opened, and means to open said second switch at a. predetermined point only in each folding cycle of the machine, and said point being determined by engagement of said second switch by a moving part of the machine which has predetermined and timed relation to the cloth folding cycle.

7. The combination in a cloth folding machine as set forth in claim 6, in which the moving part for opening the second switch comprises a cam continuously rotated in predetermined timed relation to the oscillation of the folding blade.

Lewis Jan. 20, 1925 Collier Mar. 28, 1939 

